Aqueous copolymer dispersion of polysiloxane/polyurea, cosmetic composition comprising the same, method for cosmetic treatment and method for preparation

ABSTRACT

The invention relates to an aqueous dispersion of polysiloxane/polyurea copolymer and a method for preparation thereof comprising the steps: solubilisation of the copolymer and silane in an organic phase, preparation of an aqueous phase comprising one or more surfactants, mixing the organic and aqueous phase followed by emulsification. The invention further relates to a cosmetic composition comprising said dispersion and a cosmetic treatment using said composition.

The present invention relates to aqueous dispersions of siliconecopolymers, which are especially nonionic and hydrogen-bond donors, tocosmetic compositions comprising them, and to their use in particularfor cosmetically treating the hair.

The shaping of hair is generally achieved by depositing a film-formingpolymer on the surface of the fibre, via the use of a styling product.It is important for this polymer to have good affinity for the fibre andgood styling properties, while at the same time maintaining a pleasantcosmetic feel, especially good softness and absence of tack. However,this shaping mode presents a few problems, especially in terms ofresistance over time: specifically, the polymer may become brittle underthe styling stresses; problems of water resistance: the shaping may beeliminated by washing with water or in the presence of surfactants; oralternatively problems in terms of a laden feel or a coarse and/orunnatural feel.

Moreover, compositions with a low content of volatile organic compounds(VOC) are most particularly sought.

The shaping of hair may also be performed via a chemical treatment ofthe fibre, such as permanent waving. In this case, the shaping of thehair has improved durability when compared with shaping by means of astyling product. However, this gain in durability is achieved by meansof a chemical treatment that generally intimately modifies the hairproteins and is liable to lead to more or less substantial degradationof the physicochemical properties of the fibre, especially its intrinsicsoftness, hydrophilicity and/or mechanical strength.

One of the aims of the present invention is thus to propose a means forachieving long-lasting and non-degrading shaping of the fibre,especially by virtue of the presence of a polymer dispersion, whileotherwise affording, especially by virtue of the presence of the silane,good resistance of the latex deposit (aqueous polymer dispersion), inparticular shampoo resistance, which will be reflected by betterresistance of the shaping of the hair.

It is also desired to obtain a natural appearance for the shapedhairstyle, and to improve the resistance of the deposit to mechanicalabrasion, which will be reflected especially by the better resistance tocombing (absence of appearance of particles).

The Applicants have discovered, surprisingly, that the use of an aqueousdispersion of nonionic silicone copolymer furthermore comprising asilane can provide such long-lasting shaping that is non-degrading tothe fibre and resistant.

It is known that the introduction of water into compositions comprisingnonionic silicone polymers can be difficult. Specifically, if thesilicone polymer does not bear any hydrophilic grafts and/or if highconcentrations of surfactants are not introduced into the formulation,precipitation of the silicone occurs, making its formulation impossible.

The addition of high concentrations of surfactants is not alwaysdesirable either. In particular, in leave-in applications, thesurfactant not removed may give rise to a change in the mechanicalproperties of the deposits, especially plasticization, or the appearanceof a laden feel (greasy, transferring onto the fingers) in particular inthe field of haircare.

It is known practice, in the prior art, to prepare aqueous dispersionsof silicone polymers.

Thus, document US 2005/137 327 describes the synthesis of aqueousdispersions of polyorgano-siloxane/polyurea via a process that consistsin dispersing an organopolysiloxane ending with amine groups in anacidic aqueous solution preferably comprising a surfactant, in adding adiisocyanate and then in adding a base so as to regain a neutral pH andbring about polycondensation of the amino organopolysiloxane with thediisocyanate, in order finally to obtain a polyorganosiloxane/polyureacopolymer in dispersion.

However, this approach requires the handling of diisocyanates, which maypose toxicity problems. Furthermore, the diisocyanates may react oncontact with water and form a more or less large amount of diamines thatare liable to intervene in the polymerization: this phenomenon may havean influence on the polymerization, or even may harm its control andalso the nature of the final dispersion obtained. Finally, the additionof acid in a first stage, and then of a base in a second stage, may beproblematic for compounds that are sensitive in alkaline and acidicmedium. Furthermore, this process gives rise to the formation of salts,which may harm the compositions subsequently comprising the dispersionsthus prepared.

Patent FR 2 708 199 describes the synthesis of aqueous dispersions ofanionic or cationic polyurethanes/polyureas. According to the describedprocess, it is necessary to introduce a sufficiently large quantity ofionic groups to enable dispersion of the polymer in water.

Now, it has been found that an excessive content of ionic units canresult in reduced water resistance of the polymer. Furthermore, thereare only a limited number of anionic or cationic units that can beintroduced during the synthesis, which limits the chemical diversity ofthe polyurethane or polyurea. Furthermore, the stability of the polymersprepared according to this process is dependent on the formulation pH,which may limit their formulation range.

In these documents, it is found that the polymer dispersion is generallyprepared using monomers, which are synthesized either directly in therequired solvent, or in another solvent, the synthesis then beingfollowed in the latter case by a step of changing the solvent.

The aim of the present invention is, in particular, to propose a novelprocess for preparing aqueous dispersions of silicone copolymers, thesaid dispersion being prepared from the already-formed polymer.

Moreover, the process according to the invention allows theintroduction, into the dispersion, of silane, this being a compound thatis difficult to incorporate into an aqueous polymer dispersion.Specifically, its introduction generally brings about virtuallyinstantaneous precipitation of the polymer in aqueous medium.

It has thus been discovered that it is possible to formulate highconcentrations of nonionic silicone copolymers that are hydrogen-bonddonors in the presence of a high proportion of water, this beingpossible without the mandatory addition of large amounts of surfactantsor the presence of ionic units in the copolymer.

It has also been discovered that it is possible to introduce the silaneduring the phase of constitution/preparation of the dispersion.

One subject of the present invention is thus an aqueous dispersion ofpolysiloxane/polyurea copolymer derived from the reaction between:

-   -   a) at least one polymer of formula (I) as defined below and    -   b) at least one diisocyanate-based unit; characterized in that        the said dispersion also comprises at least one silane of        structure:

as defined below.

Another subject of the invention is a cosmetic composition comprisingthe said dispersion.

Another subject of the invention is a cosmetic treatment process,especially for making up, caring for, cleansing, colouring or shapingkeratin materials, especially bodily or facial skin, the lips, thenails, the hair and/or the eyelashes, comprising the application to thesaid materials of a cosmetic composition as defined above.

Another subject of the invention is a kit in two or more parts,comprising at least one such cosmetic composition.

It has been found that the silicone copolymer dispersions according tothe invention can contain a large amount of water, which allows the easyintroduction of hydrophilic compounds into the compositions. Thesehydrophilic compounds may prove to be advantageous in terms of affordingnovel cosmetic properties.

Moreover, the properties obtained with the compositions comprising thesedispersions, in terms of deposition, are entirely different from thoseof the prior art. In particular, in the field of haircare, thesecompositions make it possible to obtain individualized hairs, whosecoating is resistant to external mechanical stresses, such as beinghandled, massaged or combed.

Furthermore, the compositions according to the invention do not requirethe use of large amounts of solvents of VOC type, for example ethanol,or of the type such as alkanes or isododecane, for example, oralternatively of silicone type, for example D5 or D6; this allowsgreater latitude of formulation.

The silicone copolymers used in the context of the invention arenonionic silicones, which are hydrogen-bond donors; they are especiallydescribed in patent application US 2005/137 327.

They may especially be derived from the reaction between:

-   -   at least one polymer of formula (I) bearing at its ends at least        one reactive function containing labile hydrogen (in particular        OH, SH, NH₂ or NHR with R=C1-C20 alkyl, C3-C40 cycloalkyl or        C6-C30 aromatic); and    -   at least one diisocyanate-based unit.

Optionally, it is also possible to react at least one additionalnonionic unit, bearing at least two reactive functions containing labilehydrogen.

The polymer of formula (I), bearing at its ends reactive unitscontaining labile hydrogen, is of the formula:

in which:

-   -   the radicals R1, which may be identical or different, are chosen        from (i) linear or branched monovalent C1-C20 hydrocarbon-based        radicals, which may be unsubstituted or substituted with        heteroatoms (in particular O, N, S or P) and (ii) C6-C30        aromatic radicals;    -   Y, which may be identical or different, represents a C1-C20        aliphatic, cycloaliphatic or aromatic hydrocarbon-based radical,        comprising at least one reactive function containing labile        hydrogen (OH, SH, NH₂ or NHR with R=C1-C20 alkyl, C3-C40        cycloalkyl or C6-C30 aromatic); and    -   n is an integer such that the average molecular weight of the        polysiloxane segment is between 300 and 10 000 g/mol and        preferably from 500 to 8000 g/mol.

As radicals R1 that are suitable for use in the context of theinvention, mention may be made more particularly of C1-C20 alkylradicals, and especially methyl, ethyl, propyl, isopropyl, butyl,pentyl, hexyl, octyl, decyl, dodecyl and octadecyl radicals; C3-C7cycloalkyl radicals, in particular the cyclohexyl radical; arylradicals, especially phenyl and naphthyl; arylalkyl radicals, especiallybenzyl and phenylethyl, and also tolyl and xylyl radicals.

Preferably, Y is chosen from the alkylene radicals of formula—(CH₂)_(a),— in which a represents an integer between 1 and 10; it beingunderstood that these radicals are substituted with at least onereactive function containing labile hydrogen, especially located at theend of the chain.

The silicones that will preferentially be chosen are those of formula:

with n such that the average molecular weight (Mw) is between 300 and 10000 g/mol.

Optionally, it is also possible to react one or more other polymersbearing reactive end groups containing labile hydrogen, chosenespecially from polyethers, polyesters, polyolefins, polycarbonates,polyamides, polyimides and polypeptides.

Obviously, a mixture of different polymers of formula (I) may bereacted.

The diisocyanate may be represented by the general formula (II):

OCN—R—NCO (II)

in which R is a linear, branched and/or cyclic, saturated orunsaturated, or even aromatic, C1-20 divalent alkylene group, which maybe unsubstituted or substituted with one or more heteroatoms (inparticular O, N, S or P).

In particular, R may be chosen from the radicals of formulae:

in which b is an integer between 0 and 3, and c is an integer between 1and 20.

The diisocyanate will preferentially be chosen from 1,6-hexamethylenediisocyanate, 1,4-tetramethylene diisocyanate,4,4′-methylenedicyclohexyl diisocyanate, 4,4′-methylenediphenyldiisocyanate, 2,4-toluene diisocyanate, 2,5-toluene diisocyanate,2,6-toluene diisocyanate, m-phenylene diisocyanate, p-phenylenediisocyanate, m-xylylene diisocyanate, tetramethyl-m-xylylenediisocyanate, naphthalene diisocyanate, butane diisocyanate, hexyldiisocyanate and isophorone diisocyanate. Needless to say, thesediisocyanates may be used alone or in the form of a mixture of two ormore diisocyanates.

The additional nonionic unit may be represented by formula (III):

X—R′—X   (III)

in which:

-   -   X, which may be identical or different, is a reactive function        containing labile hydrogen (in particular OH, SH, NH₂ or NHR        with R=C1-C20 alkyl, C3-C40 cycloalkyl or C6-C30 aromatic); and        -   R′ is a linear, branched and/or cyclic, saturated or            unsaturated C1-20 divalent alkylene group, which may be            unsubstituted or substituted with one or more heteroatoms            (in particular O, N, S or P).

Mention may be made especially of propanediol (1,2- or 1,3-),butanediol, neopentyl glycol and cyclohexanediol.

According to the invention, the copolymer is a nonionicpolysiloxane/polyurea copolymer, i.e. it does not contain any ionized orionizable groups.

Preferably, it is a block copolymer. In the context of the invention,the term “block copolymer” means a copolymer formed from at least twoblocks that are different from each of the polymers constituting thecopolymer in the backbone of the copolymer. For example, the copolymerof the invention contains at least one siloxane block and at least onepolyurea block in the copolymer backbone.

As indicated previously, the copolymer of the invention may comprise, inaddition to the polysiloxane/polyurea, other blocks of different units.Mention will be made in particular of polysiloxane/polyurea/polyurethaneblock terpolymers.

According to one particular embodiment, the copolymer contains a weightamount of polysiloxane of greater than 5%.

According to one particular embodiment, the amount of polysiloxane ispredominant in the copolymer, preferably greater than 90% by weightrelative to the total weight of the copolymer.

According to one variant, the copolymer contains solely one or moresiloxane blocks and one or more polyurea blocks.

According to the invention, the copolymer may correspond to the generalformula (IV):

in which:

-   -   R represents a monovalent hydrocarbon-based radical, where        appropriate substituted with fluorine or chlorine, containing 1        to 20 carbon atoms,    -   X represents an alkylene radical containing 1 to 20 carbon        atoms, in which non-neighbouring methylene units may be replaced        with —O— radicals,    -   A represents an oxygen atom or an amino radical

13 NR′—,

-   -   Z represents an oxygen atom or an amino radical

13 NR′—,

-   -   R′ represents hydrogen or an alkyl radical containing 1 to 10        carbon atoms,    -   Y represents a divalent hydrocarbon-based radical, where        appropriate substituted with fluorine or chlorine, containing 1        to 20 carbon atoms,    -   D represents an alkylene radical, where appropriate substituted        with fluorine, chlorine, C1-C6 alkyl or C1-C6 alkyl ester,        containing from 1 to 700 carbon atoms, in which non-neighbouring        methylene units may be replaced with —O—, —C(O)O—, —OC(O)— or        —OC(O)O— radicals,    -   n is a number ranging from 1 to 2000,    -   a is a number at least equal to 1,    -   b is a number ranging from 0 to 40,    -   c is a number ranging from 0 to 30, and    -   d is a number greater than 0,

on condition that A represents in at least one of the units (a) an NHradical.

Preferably, R represents a monovalent C1-C16 hydrocarbon-based radical,for example methyl, ethyl, vinyl and phenyl. According to one particularembodiment, R is an unsubstituted alkyl radical.

Preferably, X represents a C2-C10 alkylene radical. Preferably, thealkylene radical X is not interrupted.

According to one particular embodiment, the group A in all the units (b)and (c), when they are present, represents NH.

According to one particularly preferred embodiment, all the groups Arepresent an NH radical.

Preferably, Z represents an oxygen atom or an NH radical.

Preferably, Y represents a C3-C13 hydrocarbon-based radical, which ispreferably unsubstituted.

Preferably, Y represents a linear or cyclic aralkylene or alkyleneradical.

Preferably, D represents an alkylene radical containing at least 2 andin particular at least 4 carbon atoms, and not more than 12 carbonatoms.

Also preferably, D represents a polyoxyalkylene radical, in particular apolyoxyethylene or polyoxypropylene radical containing at least 20 andin particular at least 100 carbon atoms, and not more than 600 and inparticular not more than 200 carbon atoms.

Preferably, the radical D is unsubstituted. Preferably, n represents anumber equal to at least 3 and in particular at least 25, and preferablynot more than 800, in particular not more than 400 and particularlypreferably not more than 250.

Preferably, a represents a number greater than 50.

When b is other than 0, b preferably represents a number not greaterthan 50 and in particular not greater than 25.

Preferably, c represents a number not greater than 10 and in particularnot greater than 5.

The copolymers of the invention may be obtained according to thepolymerization processes described in patent application US 2004/0 254325 or patent application WO 03/014 194.

The copolymer may thus be obtained via a two-step process, such that:

-   -   in the first step, a silazane of formula (2) or (2′):

W representing a hydrogen atom, a substituted or unsubstitutedhydrocarbon-based radical, preferably containing from 1 to 20 carbonatoms, or a radical R₂Si—X—NH₂;

is reacted with an organosilicon compound of general formula (3):

(HO) (R₂SiO)_(n−1)[H]  (3)

to obtain an aminoalkylpolydiorganosiloxane of general formula (4):

H₂N—X—[SiR₂O]_(n)SiR₂—X—NH₂   (4)

-   -   in a second step, the aminoalkylpolydiorgano-siloxane of general        formula (4) is polymerized with a diisocyanate of general        formula (5):

OCN—Y—NCO   (5)

In general, in the first step, silazanes of general formula (2) or (2′)and reagents containing silanol groups in liquid molar proportions areused.

For the preparation of very pure silicones containing bisaminoalkyl endgroups, of general formula (4), a small excess of the silazane compoundof general formula (2) or (2′), which may then be removed, in anadditional simple process step, for instance the addition of smallamounts of water, is preferably used.

If b is at least 1, up to 95% by weight, on the basis of all of thecomponents used, of chain extenders, which are chosen from diamines,hydroxy compounds blocked with an isocyanate, dihydroxy compounds ormixtures thereof, may be used during the second step.

Preferably, the chain extenders have the general formula (6):

HZ-D-ZH   (6)

in which D and Z have the preceding meanings. If Z has the meaning O,the chain extender of general formula (6) may also be reacted before thereaction in the second step, with the diisocyanate of general formula(5). Where appropriate, water may be used as chain extender.

Examples of diisocyanates of general formula (5) to be used arealiphatic compounds such as isophorone diisocyanate, 1,6-hexamethylenediisocyanate, 1,4-tetramethylene diisocyanate and4,4′-methylene-dicyclohexyl diisocyanate or aromatic compounds, forinstance 4,4′-methylenediphenyl diisocyanate, 2,4-toluene diisocyanate,2,5-toluene diisocyanate, 2,6-toluene diisocyanate, m-phenylenediisocyanate, p-phenylene diisocyanate, m-xylylene diisocyanate,tetramethyl-m-xylylene diisocyanate, or mixtures of these isocyanates.An example of a commercially available compound is a diisocyanate of theDesmodur® series (H, I, M, T or W) from Bayer AG, Germany. Aliphaticdiisocyanates, in which Y is an alkylene radical, are preferred sincethey lead to materials that have improved UV stabilities.

The alkylenes containing α, ω-OH end groups of general formula (6) arepreferably polyalkylenes or polyoxyalkylenes. They are preferablyessentially free of contaminations of mono- or trifunctionalpolyoxyalkylenes or polyoxyalkylenes of higher functionality.Polyetherpolyols, polytetramethylene-diols, polyesterpolyols orpolycaprolactonediols, but also polyalkylenes containing α, ω-OH endgroups based on poly(vinyl acetate), poly(vinyl acetate)-ethylenecopolymers, poly(vinyl chloride) copolymers or polyisobutyldiols may beused here. Preferably, polyoxyalkyls and particularly preferablypolypropylene glycols are used. Such compounds are commerciallyavailable as base materials, inter alia, for polyurethane foams and foruses as coating, with molecular masses Mn of up to 10 000. Examples arethe polyetherpolyols and polyesterpolyols Baycoll® from Bayer AG,Germany or the polyetherpolyols Acclaim® from Lyondell Inc., USA. α,ω-Alkylenediol monomers, for instance ethylene glycol, propanediol,butanediol or hexanediol, may also be used. Moreover, for the purposesof the invention, the term “dihydroxylated compounds” also meansbishydroxyalkyl silicones, such as those sold, for example, by thecompany Goldschmidt under the names Tegomer H—Si 2111, 2311 and 2711.

The preparation of the copolymers described above of general formula (I)may be performed in solution, but also in solid form, in continuous orbatch mode.

If the amount of urethane or urea segments is large, a solvent having ahigh solubility parameter is chosen, for instance dimethylacetamide. THFmay also be used. According to one particular embodiment, the synthesisof the copolymer is performed without solvent.

The synthesis is preferably performed in the absence of moisture andunder a protective gas, usually nitrogen or argon.

The reaction is preferably performed in the presence of a catalyst. Thecatalysts that are suitable for the preparation are dialkyltincompounds, for instance dibutyltin dilaurate or dibutyltin diacetate, ortertiary amines, for instance N,N-dimethylcyclo-hexanamine,2-dimethylaminoethanol or 4-dimethylaminopyridine.

According to one particular embodiment, the copolymer that is useful inthe present invention does not contain any polyurethane.

Examples of copolymers that may be mentioned include thedimethylpolysiloxane/urea copolymer, of INCI name polyureadimethicone.

Mention may be made especially of commercial polymers such as BelsilUD-60 (Wacker SLM TPSE 60 or Geniomer 60), Belsil UD-80 (Wacker SLM TPSE80 or Geniomer 80), Wacker Belsil UD-140 (Wacker SLM TPSE 180 orGeniomer 180, and Wacker Belsil UD-200 (Wacker SLM TPSE 200 or Geniomer200) sold by the company Wacker.

Preferably, the copolymers according to the invention have anumber-average molecular mass (Mn) of between 1000 and 5 000 000,especially between 2000 and 1 000 000 and more preferentially between2000 and 100 000 g/mol.

The use of these copolymers as an aqueous dispersion, in the presence ofsilane, requires a dispersion process, or a process of preparing thedispersion, that preferably comprises the following steps:

-   -   dissolution of the copolymer and the silane in an organic phase        composed of one or more cosmetic oils and/or solvents;    -   addition of the said organic phase comprising the polymer to an        aqueous phase comprising one or more surfactants, followed by        emulsification with rapid stirring.

Optionally, all or some of the cosmetic oils or solvents used todissolve the polymer may be evaporated off via any technique consideredappropriate by a person skilled in the art, such as evaporation undervacuum.

An aqueous dispersion of silicone copolymer that is stable over time(absence of macroscopic phase separation after 5 days at roomtemperature) may thus be obtained, the said dispersion also comprising asilane.

As cosmetic oil or solvent that may be used in the context of theinvention, mention may be made of any liquid compound (at 20-25° C., 1atm.) that is insoluble in water and solubilizing for the copolymer.

The term “insoluble in water” refers to a compound whose solubility inwater (at 25° C., 1 atm.) is less than 1% by weight.

The term “solubilizing for the copolymer” refers to a compound thatenables the dissolution of at least 1% by weight of polymer (at 25° C.,1 atm.).

Preferably, at least one solvent compound with a boiling point of lessthan 150° C., at 1 atm., and/or a solvent compound that can form anazeotrope with water, is used.

Mention may be made especially of the following compounds, it beingunderstood that they are liquid at 20-25° C., 1 atm.:

-   -   linear or branched, saturated or unsaturated, optionally cyclic        or aromatic C5-C30 alcohols or polyols, which may contain        heteroatoms (O, N, P or S); and more particularly saturated,        linear or branched C5-C30 alcohols or polyols; or even        saturated, linear or branched C5-C20 alcohols or polyols;        preferentially monoalcohols;    -   esters of monoalcohols or polyols and of monoacids or polyacids,        and in particular triglycerides such as plant oils and esters of        general formula R3-O— CO-R4, in which R3 and R4, which may be        identical or different, are linear or branched, or even cyclic,        saturated or unsaturated, preferably C3-C30 or even C4-C20 alkyl        hydrocarbon-based radicals; in particular, R3 is preferably a        C1-C6 or even C2-C4 alkyl; in particular, R4 is preferably a        C1-C18 or even C1-C15 alkyl;    -   ketones of the type R3-CO-R4 in which R3 and R4, which may be        identical or different, are linear or branched, or even cyclic,        saturated or unsaturated, preferably C3-C30 alkyl        hydrocarbon-based radicals; preferentially, R3 and R4 are linear        or branched C4-C8 alkyls;    -   aromatic hydrocarbons, such as toluene;    -   linear, cyclic or branched C5-C30 alkanes; preferably C6-C20,        better still C10-C16, or even C11-C13;    -   volatile or non-volatile silicone oils; mention may be made        especially of polydimethylsiloxanes (PDMS), phenylated        polyorganosiloxanes such as phenyl trimethicones,        phenyltrimethylsiloxydiphenylsiloxanes,        diphenylmethyldimethyltrisiloxanes, diphenyl dimethicones,        phenyl dimethicones and polymethylphenyl-siloxanes, which are        optionally fluorinated; polysiloxanes modified with fatty acids,        fatty alcohols or polyoxyalkylenes, fluoro silicones and        perfluoro silicone oils.

Among the preferred silicone oils, mention may be made ofpolydimethylsiloxanes, polymethylphenyl-siloxanes, silicones comprisingpolyoxyalkylene blocks or grafts, in particular polyoxyalkylene orcopoly(oxyethylene/oxypropylene) such as dimethicone copolyols,silicones bearing both hydrocarbon-based hydrophobic groups (for exampleC₂-C₃₀ alkyl groups) and polyoxyethylene orcopoly(oxyethylene/oxypropylene) blocks or grafts such asalkyldimethicone copolyols, silicones bearing fluoro or perfluorogroups, such as perfluoroalkyl polydimethylsiloxanes and perfluoroalkylpolymethylphenylsiloxanes, and mixtures thereof. These silicone oils mayoptionally comprise alkyl or alkoxy groups at the end of the siliconechain or pendent thereon.

Mention may also be made of linear or cyclic silicones, in particularcomprising from 2 to 7 silicon atoms. Mention may be made especially ofoctamethylcyclotetrasiloxane, decamethylcyclopenta-siloxane,hexadecamethylcyclopentasiloxane, hepta-methylhexyltrisiloxane andheptamethyloctyltrisiloxane, and mixtures thereof.

Among these solvents, ethyl acetate, butyl acetate, propyl acetate,isopropyl acetate, isopropyl palmitate, pentanol, hexanol, heptanol,heptane, decane, dodecane, isododecane, undecane, tridecane,cyclotetramethylsiloxane (D4), cyclopentamethylsiloxane (D5),cyclohexamethylsiloxane (D6), methyl ethyl ketone and toluene; and alsomixtures thereof, will preferentially be chosen.

Needless to say, a mixture of solvents may be employed.

In one particular embodiment, a solvent of linear or branched C5-C20alcohol type is used, alone or as a mixture with a C5-C20 alkane, acyclic volatile silicone oil and/or a C4-C20 ester, which are themselvesalone or as a mixture.

The surfactants that may be used may be anionic, cationic, amphoteric ornonionic; a mixture of surfactants may be used.

Preferably, the surfactants are cationic or anionic, preferentiallycationic.

Mention may thus be made of the following anionic surfactants, which maybe used alone or as mixtures: salts, in particular alkali metal saltssuch as sodium salts, ammonium salts, amine salts, amino alcohol saltsor alkaline-earth metal salts, for example magnesium salts, of thefollowing compounds: alkyl sulfates, alkyl ether sulfates, alkylamidoether sulfates, alkylaryl polyether sulfates, monoglyceride sulfates,alkyl sulfonates, alkyl phosphates, alkylamide sulfonates, alkylarylsulfonates, α-olefin sulfonates, paraffin sulfonates, alkylsulfosuccinates, alkyl ether sulfosuccinates, alkylamidesulfosuccinates, alkyl sulfoacetates, acyl sarcosinates and acylglutamates, the alkyl and acyl groups of all these compounds containingfrom 6 to 24 carbon atoms, and the aryl group preferably denoting aphenyl or benzyl group. It is also possible to use esters of C₆-C₂₄alkyl and of polyglycoside-carboxylic acids, such as alkyl glucosidecitrates, polyalkyl glycoside tartrates and polyalkyl glycosidesulfosuccinates; alkyl sulfosuccinamates, acyl isethionates andN-acyltaurates, the alkyl or acyl group of all these compoundscontaining from 12 to 20 carbon atoms. Among the anionic surfactantsthat may also be used, mention may also be made of acyl lactylates inwhich the acyl group contains from 8 to 20 carbon atoms. In addition,mention may also be made of alkyl-D-galactosideuronic acids and saltsthereof, and also polyoxyalkylenated (C₆-C₂₄ alkyl)ethercarboxylicacids, polyoxyalkylenated (C₆-C₂₄ alkyl) (C₆-C₂₄ aryl)ethercarboxylicacids and polyoxyalkylenated (C₆-C₂₄ alkyl)amidoethercarboxylic acidsand salts thereof, in particular those comprising from 2 to 50 ethyleneoxide groups, and mixtures thereof.

Among the preferred anionic surfactants, mention may be made of thesalts, in particular of sodium, of magnesium or of ammonium, of alkylsulfates; of alkyl ether sulfates, for instance sodium lauryl ethersulfate, preferably containing 2 or 3 mol of ethylene oxide; of alkylether carboxylates; and mixtures thereof, the alkyl groups generallycontaining from 6 to 24 carbon atoms and preferably from 8 to 16 carbonatoms.

As nonionic surfactants that may be used in the composition according tothe invention, mention may be made of polyethoxylated, polypropoxylatedor polyglycerolated fatty acids, (C₁-C₂₀)alkylphenols, α-diols oralcohols, having a fatty chain containing, for example, 8 to 18 carbonatoms, it being possible for the number of ethylene oxide or propyleneoxide groups to range in particular from 2 to 50 and for the number ofglycerol groups to range in particular from 2 to 30. Mention may also bemade of copolymers of ethylene oxide and of propylene oxide, condensatesof ethylene oxide and of propylene oxide with fatty alcohols;polyethoxylated fatty amides preferably having from 2 to 30 mol ofethylene oxide, polyglycerolated fatty amides containing on average 1 to5, and in particular 1.5 to 4, glycerol groups; polyethoxylated fattyamines preferably having 2 to 30 mol of ethylene oxide; oxyethylenatedfatty acid esters of sorbitan having from 2 to 30 mol of ethylene oxide;fatty acid esters of sucrose, fatty acid esters of polyethylene glycol,(C₆-C₂₄)alkylpolyglycosides, N-(C₆-C₂₄)alkylglucamine derivatives, amineoxides such as (C₁₀-C₁₄) alkylamine oxides orN-(C₁₀-C₁₄)acylaminopropylmorpholine oxides; and mixtures thereof.

Among the amphoteric surfactants, mention may be made of aliphaticsecondary or tertiary amine derivatives, in which the aliphatic group isa linear or branched chain containing 8 to 22 carbon atoms andcontaining at least one water-soluble anionic group, such as, forexample, a carboxylate, sulfonate, sulfate, phosphate or phosphonategroup; mention may also be made of (C₈-C₂₀)alkylbetaines, sulfobetaines,(C₈-C₂₀) alkylamido (C₆-C₈) alkylbetaines or (C₈-C₂₀)alkyl-amido(C₆-C₈)alkylsulfobetaines; and mixtures thereof. Among theamine derivatives that may be mentioned are the products sold under thename Miranol®, as described in patents U.S. Pat. No. 2,528,378 and U.S.Pat. No. 2,781,354 and classified in the CTFA dictionary, 3rd edition,1982, under the names Amphocarboxyglycinate and amphocarboxypropionate,having the respective structures (2) and (3):

R₂—CONHCH₂CH₂—N⁺(R₃)(R₄)(CH₂COO⁻)   (2)

in which:

R₂ represents an alkyl group derived from an acid R₂—COOH present inhydrolysed coconut oil, or a heptyl, nonyl or undecyl group,

R₃ represents a β-hydroxyethyl group, and

R₄ represents a carboxymethyl group; and

R_(2′)—CONHCH₂CH₂—N(B)(C)   (3)

in which:

B represents —CH₂CH₂OX′,

C represents —(CH₂)_(z)-Y′, with z=1 or 2,

X′ represents the —CH₂CH₂—COOH group or a hydrogen atom,

Y′ represents —COOH or the —CH₂—CHOH—SO₃H group,

R₂, represents the alkyl group of an acid R₉—COOH present in coconut oilor in hydrolysed linseed oil, an alkyl group, especially a C₁₇ group andits iso form, or an unsaturated C₁₇ group.

These compounds are classified in the CTFA dictionary, 5th edition,1993, under the names disodium cocoamphodiacetate, disodiumlauroamphodiacetate, disodium caprylamphodiacetate, disodiumcapryloampho-diacetate, disodium cocoamphodipropionate, disodiumlauroamphodipropionate, disodium caprylampho-dipropionate, disodiumcapryloamphodipropionate, lauroamphodipropionic acid,cocoamphodipropionic acid.

By way of example, mention may be made of the cocoamphodiacetate soldunder the trade name Miranol® C2M Concentrate by the company Rhodia.

Among the amphoteric surfactants that are preferably used are (C₈-C₂₀)alkylbetaines, (C₈-C₂₀)alkyl-amido(C₆-C₉)alkylbetaines andalkylamphodiacetates, and mixtures thereof.

Among the cationic surfactants, mention may be made of:

i) alkylpyridinium salts, ammonium salts of imidazoline, diquaternaryammonium salts, and ammonium salts containing at least one esterfunction;

ii) quaternary ammonium salts having the following general formula:

in which the radicals R1 to R4, which may be identical or different,represent a linear or branched aliphatic radical containing from 1 to 30carbon atoms, or an aromatic radical such as aryl or alkylaryl; thealiphatic radicals may optionally comprise heteroatoms (O, N, S orhalogens).

The aliphatic radicals are chosen, for example, from C12-C22 alkyl,alkoxy, C2-C6 polyoxyalkylene, alkylamide,(C12-C22)alkylamido(C2-C6)alkyl, (C12-C22)alkylacetate and hydroxyalkylradicals, containing from about 1 to 30 carbon atoms.

X⁻ is an anion chosen from the group of halides, phosphates, acetates,lactates, C2-C6 alkyl sulfates and alkyl- or alkylaryl-sulfonates.

iii) quaternary ammonium salts of imidazoline of formula :

in which:

-   -   R5 represents an alkenyl or alkyl radical containing from 8 to        30 carbon atoms, for example fatty acid derivatives of tallow or        of coconut,    -   R6 represents a hydrogen atom, a C1-C4 alkyl radical or an        alkenyl or alkyl radical containing from 8 to 30 carbon atoms,    -   R7 represents a C1-C4 alkyl radical,    -   R8 represents a hydrogen atom or a C1-C4 alkyl radical,    -   X is an anion chosen from the group of halides, phosphates,        acetates, lactates, C2-C6 alkyl sulfates, alkylsulfonates or        alkylarylsulfonates.

R5 and R6 preferably denote a mixture of alkenyl or alkyl radicalscontaining from 12 to 21 carbon atoms, such as, for example, fatty acidderivatives of tallow, R7 denotes methyl and R8 denotes hydrogen. Such aproduct is, for example, Quaternium-27 (CTFA 1997) or Quaternium-83(CTFA 1997), which are sold under the names Rewoquat® W75, W90, W75PGand W75HPG by the company Witco,

iv) diquaternary ammonium salts of formula:

in which:

-   -   R9 denotes an aliphatic radical containing from about 16 to 30        carbon atoms,    -   R10, R11, R12, R13 and R14, which may be identical or different,        are chosen from hydrogen and an alkyl radical containing from 1        to 4 carbon atoms, and    -   X⁻ is an anion chosen from the group of halides, acetates,        phosphates, nitrates and methyl sulfates. Such diquaternary        ammonium salts in particular comprise propanetallowdiammonium        dichloride;

v) quaternary ammonium salts containing at least one ester function,such as those of formula :

in which:

-   -   R15 is chosen from C1-C6 alkyl radicals and C1-C6 hydroxyalkyl        or dihydroxyalkyl radicals;    -   R16 is chosen from the radical R19—CO—, linear or branched,        saturated or unsaturated C1-C22 hydrocarbon-based radicals R20,        a hydrogen atom;    -   R18 is chosen from the radical R21-CO—, linear or branched,        saturated or unsaturated C1-C22 hydrocarbon-based radicals R22,        a hydrogen atom;    -   R17, R19 and R21, which may be identical or different, are        chosen from linear or branched, saturated or unsaturated C7-C21        hydrocarbon-based radicals;    -   r, n and p, which may be identical or different, are integers        ranging from 2 to 6;    -   y is an integer ranging from 1 to 10;    -   x and z, which may be identical or different, are integers        ranging from 0 to 10;    -   X⁻is a simple or complex organic or mineral anion;

with the proviso that the sum x+y+z is from 1 to 15, that when x is 0,then R16 denotes R20 and that when z is 0, then R18 denotes R22.

The alkyl radicals R15 may be linear or branched, and more particularlylinear. Preferably, R15 denotes a methyl, ethyl, hydroxyethyl ordihydroxypropyl radical, and more particularly a methyl or ethylradical.

Advantageously, the sum x+y+z is from 1 to 10.

When R16 is a hydrocarbon-based radical R20, it may contain from 12 to22 carbon atoms, or contain from 1 to 3 carbon atoms.

When R18 is a hydrocarbon-based radical R22, it preferably contains 1 to3 carbon atoms.

Advantageously, R17, R19 and R21, which may be identical or different,are chosen from linear or branched, saturated or unsaturated C11-C21hydrocarbon-based radicals, and more particularly from linear orbranched, saturated or unsaturated C11-C21 alkyl and alkenyl radicals.

Preferably, x and z, which may be identical or different, are 0 or 1.Advantageously, y is equal to 1.

Preferably, r, n and p, which may be identical or different, are equalto 2 or 3 and even more particularly equal to 2.

The anion X⁻ is preferably a halide (chloride, bromide or iodide) or aC1-C4 alkyl sulfate, more particularly methyl sulfate. However, theanion X⁻ may also represent methanesulfonate, phosphate, nitrate,tosylate, an anion derived from an organic acid (such as acetate orlactate), or any other anion that is compatible with the ammoniumcontaining an ester function.

The surfactants may be, for example, the salts (chloride or methylsulfate) of diacyloxyethyl-dimethylammonium, ofdiacyloxyethylhydroxyethyl-dimethylammonium, ofmonoacyloxyethylhydroxyethyl-dimethylammonium, oftriacyloxyethylmethylammonium, ofmonoacyloxyethylhydroxyethyldimethylammonium, and mixtures thereof. Theacyl radicals preferably contain 14 to 18 carbon atoms and are moreparticularly derived from a plant oil, for instance palm oil orsunflower oil. When the compound contains several acyl radicals, theseradicals may be identical or different. Such compounds are sold, forexample, under the names Dehyquart® by the company Cognis, Stepanquat®by the company Stepan, Noxamium® by the company Ceca, and Rewoquat® WE18 by the company Rewo-Goldschmidt.

vi) quaternary ammonium salts and in particular behenyltrimethylammoniumchloride, dipalmitoylethyl hydroxyethyl methyl ammonium methosulfate,cetyltrimethylammonium chloride, quaternium-83,behenylamidopropyl-2,3-dihydroxypropyldimethylammonium chloride andpalmitylamidopropyltrimethylammonium chloride.

The silane present in the aqueous dispersion is of structure:

in which:

-   -   X represents a C1-C6 alkoxy group, more particularly ethoxy;    -   Y represents a C1-C6 alkoxy group, more particularly ethoxy; or        C1-C6 alkyl, more particularly methyl;    -   Z is a linear or branched, saturated or unsaturated C1-C22        hydrocarbon-based chain, which may be substituted with an amine        group NH₂ or NHR (R═C1-C20 and especially C1-C6 alkyl, C3-C40        cycloalkyl or C6-C30 aromatic); or with a hydroxyl group, a        thiol group, an aryl group (more particularly benzyl), which is        substituted or unsubstituted; Z possibly being interrupted with        a heteroatom (O, S or NH) or a carbonyl group (CO);    -   n represents an integer equal to 1 or 2.

Examples that may be mentioned includeN-(3-acryloxy-2-hydroxypropyl)-3-aminopropyltriethoxysilane,4-aminobutyltriethoxysilane, 3-aminopropylmethyl-diethoxysilane,3-aminopropyltriethoxysilane,3-aminopropyltris(methoxyethoxyethoxy)silane,bis(methyl-diethoxysilylpropyl)amine,bis[3-(triethoxysilyl)-propyl]urea,3-(2,4-dinitrophenylamino)propyltriethoxy-silane,hydroxymethyltriethoxysilane, mercapto-methylmethyldiethoxysilane,3-mercaptopropyl-triethoxysilane,o-(methacryloxyethyl)-N-(triethoxy-silylpropyl)urethane,N-(3-methacryloxy-2-hydroxy-propyl)-3-aminopropyltriethoxysilane,o-(propargyloxy)-N-(triethoxysilylpropyl)urethane,(3-triethoxysilyl-propyl)-t-butylcarbamate,triethoxysilylpropylethyl-carbamate,N-(3-triethoxysilylpropyl)gluconamide,N-(3-triethoxysilylpropyl)-4-hydroxybutyramide,3-(triethoxysilylpropyl)-p-nitrobenzamide,N-(triethoxy-silylpropyl)-O-polyethylene oxide urethane,ureido-propyltriethoxysilane ando-(vinyloxyethyl)-N-(triethoxysilylpropyl)urethane, and mixturesthereof.

The silane may serve to promote the attachment of the copolymer to thekeratin support.

The silane, alone or as a mixture, may be present in a proportion offrom 0.5% to 30% by weight, especially 1% to 25% by weight or even 2% to20% by weight, relative to the weight of the dispersion.

Other ingredients may be present in the aqueous dispersion of siliconecopolymer according to the invention; these ingredients may beintroduced into the aqueous phase or the organic phase, during thepreparation of the dispersion.

Mention may thus be made of the following, alone or as a mixture:cationic, anionic and/or nonionic silicones bearing hydrophilic orhydrophobic grafts; plasticizers; spreading agents or coalescers; solidfatty substances such as fatty alcohols, fatty acids or plant or mineralwaxes; conditioning agents, especially of cationic polymer typeincluding polyamines; anionic (neutralized or non-neutralized), cationicor nonionic polymers and especially styling polymers; pH agents, basesor acids; organic or mineral pigments or colorants; sunscreens,fragrances, peptizers, preserving agents, amino acids or vitamins; andthickeners

As has been mentioned hereinabove, a process for preparing the aqueousdispersions of polysiloxane/polyurea according to the inventioncomprises the following steps:

-   -   i) dissolving the copolymer and the silane in an organic phase;

Preferably, the copolymer is present in a proportion of from 2% to 60%by weight, especially 5% to 40% by weight or even 8% to 25% by weight,in the organic phase.

-   -   ii) preparing an aqueous phase comprising one or more        surfactants;

Preferably, the surfactant(s) are present in a proportion of from 0.01%to 15% by weight, especially 0.05% to 10% by weight or even 0.1% to 6%by weight, in the aqueous phase.

-   -   iii) mixing together the organic and aqueous phases, and then        emulsifying, especially with rapid stirring;

Preferably, the surfactant represents 0.01% to 15% by weight, especially0.05% to 10% by weight or even 0.1% to 5% by weight relative to theweight of the organic phase comprising the copolymer.

Preferably, 0.5 to 50 parts by weight and in particular 0.8 to 20 partsof aqueous phase comprising the surfactants are added, especially 1 to12 parts, or even 2 to 8 parts, per 1 part of organic phase comprisingthe copolymer.

Preferably, the emulsification is performed at a temperature from 15 to100° C., especially 18 to 50° C., or even 20-30° C., at a speed ofbetween 50 and 30 000 rpm and especially 200 to 10 000 rpm, via anymeans known to those skilled in the art, especially with an homogenizer,in particular of the Ultra-Turrax type.

Optionally, all or part of the organic phase may then be evaporated, viaany technique considered adequate by a person skilled in the art, suchas evaporation under reduced pressure (under vacuum).

It is thus possible finally to obtain an aqueous dispersion ofpolysiloxane/polyurea copolymer, whose solids content may be between0.1% and 50% by weight, especially 0.5% to 40% by weight, or even 1% to30% by weight and better still 2% to 25% by weight.

The dispersion according to the invention may comprise solvent compoundsand/or an organic phase, which may represent 0.05% to 80% by weight andespecially 1% to 70% by weight of the said dispersion. This organicphase may also be absent (less than 0.05%, or even 0%).

The dispersion may also comprise surfactants, which may represent 0.05%to 10% by weight, especially 0.01% to 8% by weight or even 0.1% to 5% byweight of the said dispersion. These surfactants may also be absent(less than 0.05%, or even 0%).

The aqueous dispersion according to the invention finds a quiteparticular application in the field of cosmetics, especially in thefield of haircare.

The amount of polymer present in the compositions obviously depends onthe type of composition and on the desired properties; it may rangebetween 0.01% and 30% by weight, preferably between 0.1% and 20% byweight, especially between 0.5% and 10% by weight, or even between 1%and 5% by weight of polymer solids relative to the weight of thecosmetic composition.

The compositions according to the invention may be in any galenical formconventionally used for topical application, and especially in the formof an aqueous, alcoholic or aqueous-alcoholic solution or suspension; anoily solution or suspension; a solution or dispersion of the lotion orserum type; an emulsion of liquid or semi-liquid consistency of the milkor cream type, obtained by dispersing a fatty phase in an aqueous phase(O/W) or, conversely, (W/O); an aqueous or anhydrous gel, an ointment, aloose or compact powder to be used in this form or to be incorporatedinto an excipient, or any other cosmetic form. These compositions may bepackaged, especially in pump bottles or in aerosol containers, so as toapply the composition in vaporized form or in the form of a mousse. Suchpackaging forms are indicated, for example, when it is desired to obtaina spray or a mousse for treating the hair. The compositions inaccordance with the invention may also be in the form of creams, gels,emulsions, lotions or waxes. When the composition according to theinvention is packaged in the form of an aerosol in order to obtain alacquer or a mousse, it comprises at least one propellant.

The compositions according to the invention comprise a cosmeticallyacceptable medium, i.e. a medium that is compatible with keratinmaterials, especially facial or bodily skin, the lips, the hair, theeyelashes, the eyebrows and the nails.

Depending on their nature and the intended use of the composition, theingredients of the cosmetically acceptable medium may be present inusual amounts, which may be readily determined by a person skilled inthe art, and which may be, for each ingredient, between 0.01% and 80% byweight.

Mention may be made especially of the following ingredients, alone or asa mixture: nonionic, cationic, anionic or amphoteric surfactants;hydrophilic solvents (alcohols) or hydrophobic solvents (alkanes);cationic, anionic or nonionic silicones bearing hydrophilic orhydrophobic grafts, which may or may not be phenylated; plasticizers,for example of polyol type; spreading agents or coalescers; silanes,especially those having the structure described above; liquid or solidfatty substances such as fatty alcohols, fatty acids, plant or mineraloils and plant or mineral waxes; conditioning agents such as cationicpolymers including polyamines; polymers, especially styling polymers,which are in particular anionic (neutralized or non-neutralized),cationic or nonionic; pH agents (bases or acids); organic or mineralpigments or colorants; fillers such as nacres, TiO₂, resins and clays;sunscreens; fragrances; peptizers; preserving agents; amino acids;vitamins.

The cosmetic composition according to the invention may be in the formof a product for caring for, cleansing and/or making up bodily or facialskin, the lips, the eyebrows, the eyelashes, the nails and the hair, anantisun or self-tanning product, a body hygiene product, or a haircareproduct, especially for caring for, cleansing, styling, shaping orcolouring the hair.

The composition especially finds a particularly advantageous use in thefield of haircare, especially for holding the hairstyle or shaping thehair, or for the care, cosmetic treatment or cleansing of the hair. Thehaircare compositions are preferably shampoos, hair conditioners,styling or care gels, care lotions or creams, conditioners, hairsettinglotions, blow-drying lotions, hair styling and fixing compositions suchas lacquers or sprays; hair restructuring lotions; lotions or gels forpreventing hair loss, antiparasitic shampoos, antidandruff lotions orshampoos, and anti-seborrhoea treating shampoos. The lotions may bepackaged in various forms, especially in vaporizers, in pump bottles orin aerosol containers so as to apply the composition in vaporized formor in the form of a mousse.

The composition may also be in the form of a hair colouring product,especially an oxidation dye or direct dye, optionally in the form ofcolouring shampoos; in the form of a permanent-waving, relaxing orbleaching composition, or alternatively in the form of a rinse-outcomposition, to be applied before or after dyeing, bleaching,permanent-waving or relaxing the hair, or alternatively between the twosteps of a permanent-waving or relaxing operation.

The composition according to the invention may also be in the form of acare composition, especially a moisturizer, for bodily or facial skin,the lips and/or the integuments, especially a care product forcosmetically treating the skin and especially for moisturizing it,making it smooth, depigmenting it, nourishing it, protecting it againstsunlight, or giving it a specific cosmetic treatment. Thus, it may be alipcare base, a fixing base for lipsticks, an antisun or artificialtanning composition, a facial care composition (a day, night,anti-ageing or moisturizing composition); a matting composition; a skincleansing composition, for example a makeup-removing product or a bathor shower gel, or a cleansing bar or soap; a body hygiene composition,especially a deodorant or antiperspirant product, or alternatively ahair-removing composition or an aftershave gel or lotion. It may also bein the form of a makeup product for bodily or facial skin, the lips, theeyelashes, the nails or the hair; in particular a foundation, a blusher,a makeup rouge, an eyeshadow, a concealer product, an eyeliner, amascara, a lipstick, a lip gloss, a lip pencil; a nail varnish, anailcare product; a temporary tattoo product for bodily skin.

Even more particularly, the composition according to the invention findsan advantageous application in holding the hairstyle or shaping thehair, or alternatively in caring for, cosmetically treating or cleansingthe hair.

One subject of the invention is thus a cosmetic treatment process,especially for making up, caring for, cleansing, colouring or shapingkeratin materials, especially bodily or facial skin, the lips, thenails, the hair and/or the eyelashes, comprising the application to thesaid materials of a cosmetic composition comprising at least onecompound according to the invention.

Preferably, it is a cosmetic treatment process for conditioning thehair, in particular to give it or improve its suppleness, disentangling,smoothing, combability and manageability.

The application of the composition may optionally be followed by a heattreatment step.

The composition may also be in the form of a kit in two or more parts.

These parts may be intended for mixing together at the time of use oralternatively for application successively to the keratin substrate tobe treated, in particular the hair. These successive application stepsmay or may not be interrupted by a step of manual drying, for examplewith a towel, or by means of an appliance, for instance a hairdryer.

In one preferred case of the invention, the composition comprising thedispersion according to the invention is used in leave-in mode.

In one preferred case of the invention, the composition comprising thedispersion according to the invention is used in combination with aheating appliance for shaping the hair, such as a curling iron, a wavingiron, a crimping iron, a straightening iron or heated curlers. Thetemperature of the heating appliance used is preferably between 60° C.and 200° C.

In one preferred embodiment, the composition according to the inventionmay be applied to wet or dry hair, a step optionally followed by partialor total drying of the hair, optionally followed by the application of aheating tool, which may be a hairdryer or a tool for simultaneouslyapplying a mechanical constraint and heating (straightening iron, wavingiron, crimping iron or curling iron, using or not using steam). Thetemperature of the tool is preferably between 60° C. and 200° C.

The invention is illustrated in greater detail in the examples thatfollow.

EXAMPLE 1

A polysiloxane/polyurea copolymer (Belsil UD80) andaminopropyltriethoxysilane (APTES) are dissolved in hexanol. Thissolution is added to an aqueous solution of cationic surfactant(cetyltrimethylammonium chloride) diluted in water and stirred with anUltra-Turrax blender at 13 000 rpm. The mixture is homogenized for 30minutes and the hexanol is then removed on a rotary evaporator. Anopaque white aqueous dispersion is thus obtained, the composition ofwhich is given below.

Copoly- Organic Surfac- mer APTES phase tant Water Disper- Before 20 g  22 g 140 g 4.8 g 1964 g sion (1) evaporation Hexanol After 7.8%  8.6%0% 1.9% 81.7% evaporation Disper- Before 20 g 53.3 g 140 g 4.8 g 1964 gsion (2) evaporation Hexanol After 7.1% 18.8% 0% 1.7% 72.4% evaporationDisper- Before 20 g 53.3 g 140 g 4.8 g 1964 g sion (3) evaporationHexanol After 7.2% 19.1% 0% 1.7% 72.0% evaporation Disper- Before 20 g106.6 g  140 g 4.8 g 1964 g sion (4) evaporation Hexanol After 4.9%26.1% 0% 1.2% 67.8% evaporation

EXAMPLE 2

The following compositions are prepared (weight %):

compo- composition 1 composition 2 composition 3 sition 4 Dispersion 48%— — — (1) Dispersion — 53% — — (2) Dispersion — — 52% — (3) Dispersion —— — 76.5% (4) lactic qs pH 10 qs pH 10 qs pH 10 qs pH 10 acid deionizedqs 100% qs 100% qs 100% qs 100% water

1 g of composition is deposited on a lock of 2.7 g of natural hair.After drying, shaping is performed using a heating tool such as acurling iron, applied for 30 seconds, with the thermostat set for atemperature of between 140 and 180° C. After cooling, the lock issuspended in ambient medium. The shape setting and its hold over timeare evaluated, at T0 and after 6 shampoo washes.

The resistance of the coating to shampooing is evaluated in thefollowing manner: 1 g of Ultra Doux shampoo from Garnier is deposited onthe prewetted lock; the lock is massaged from the root to the end inpasses; the lock is then rinsed in water for 10 seconds. The operationis repeated six times in a row. After drying, the iron is reapplied andthe lock is again suspended for evaluation of the shape.

The comparative composition only contains water.

A tighter shape, which holds well over time, is obtained with thecompositions according to the invention; this effect is also resistantafter 6 shampoo washes.

1. An aqueous dispersion of polysiloxane/polyurea copolymer obtainedfrom a reaction between: a) at least one polymer of formula (I) bearingat its ends at least one reactive function containing labile hydrogen:

wherein: the radicals R1, identical or different, are selected from thegroup consisting of (i) linear or branched monovalent C1-C20hydrocarbon-based radicals, which are optionally unsubstituted orsubstituted with heteroatoms and (ii) C6-C30 aromatic radicals; Y, whichis optionally identical or different, represents a C1-C20 aliphatic,cycloaliphatic or aromatic hydrocarbon-based radical, comprising atleast one reactive function containing labile hydrogen; and n is aninteger wherein an average molecular weight of the polysiloxane segmentis between 300 and 10 000 g/mol; and b) at least one diisocyanatederivative; wherein the said dispersion comprises at least one silane ofstructure:

wherein: X represents a C1-C6 alkoxy group; Y is a C1-C6 alkoxy or C1-C6alkyl group; Z is a linear or branched, saturated or unsaturated C1-C22hydrocarbon-based chain, which is optionally substituted with an aminegroup NH₂ or NHR (R═C1-C20 alkyl, C3-C40 cycloalkyl or C6-C30 aromatic);or with a hydroxyl group, a thiol group, or a substituted orunsubstituted aryl group; Z optionally being interrupted with aheteroatom or a carbonyl group (CO); n represents an integer equal to 1or
 2. 2. The dispersion according to claim 1, wherein the copolymerfurther comprises at least one additional nonionic unit bearing at leasttwo reactive functions containing labile hydrogen.
 3. The dispersionaccording to claim 1, wherein the copolymer is a block copolymer.
 4. Thedispersion according to claim 1, wherein the polymer is of generalformula (IV):

wherein: R represents a monovalent hydrocarbon-based radical, whereappropriate substituted with fluorine or chlorine, containing 1 to 20carbon atoms, X represents an alkylene radical containing 1 to 20 carbonatoms, wherein non-neighbouring methylene units are optionally replacedwith —O— radicals, A represents an oxygen atom or an amino radical—NR′—, Z represents an oxygen atom or an amino radical —NR′—, R′represents hydrogen or an alkyl radical containing 1 to 10 carbon atoms,Y represents a divalent hydrocarbon-based radical, where appropriatesubstituted with fluorine or chlorine, containing 1 to 20 carbon atoms,D represents an alkylene radical, where appropriate substituted withfluorine, chlorine, C1-C6 alkyl or C1-C6 alkyl ester, containing from 1to 700 carbon atoms, wherein non-neighbouring methylene units areoptionally replaced with —O—, —C(O)O—, —OC(O)— or —OC(O)O— radicals, nis a number ranging from 1 to 2000, a is a number at least equal to 1, bis a number ranging from 0 to 40, c is a number ranging from 0 to 30,and d is a number greater than 0, wherein A represents in at least oneof the units (a) an NH radical.
 5. The dispersion according to claim 1,wherein the silane is, alone or as a mixture, selected from the groupconsisting ofN-(3-acryloxy-2-hydroxypropyl)-3-aminopropyltriethoxysilane,4-aminobutyltriethoxysilane, 3-aminopropylmethyldiethoxysilane,3-aminopropyltriethoxysilane,3-aminopropyltris(methoxyethoxyethoxy)silane,bis(methyldiethoxysilylpropyl)amine, bis[3-(triethoxysilyl)propyl]urea,3-(2,4-dinitrophenylamino)propyltriethoxysilane,hydromethyltriethoxysilane, mercaptomethylmethyldiethoxysilane,3-mercaptopropyltriethoxysilane,o-(methacryloxyethyl)-N-(triethoxysilylpropyl)urethane,N-(3-methacryloxy-2-hydroxypropyI)-3-aminopropyltriethoxysilane,o-(propargyloxy)-N-(triethoxysilylpropyl)urethane,(3-triethoxysilylpropyl)-t-butylcarbamate,triethoxysilylpropylethylcarbamate,N-(3-triethoxysilylpropyl)gluconamide,N-(3-triethoxysilylpropyl)-4-hydroxybutyramide,3-(triethoxysilylpropyl)-p-nitrobenzamide,N-(triethoxysilylpropyl)-O-polyethylene oxide urethane,ureidopropyltriethoxysilane and o-(vinyloxyethyl)-N-(triethoxysilylpropyl)urethane.
 6. The dispersion according to claim 1, wherein thesilane, alone or as a mixture, is present in a proportion of from 0.5%to 30% by weight, relative to the weight of the dispersion.
 7. Thedispersion according to claim 1, which is optionally obtained via adispersion process comprising: dissolving the copolymer and the silanein an organic phase, preparing an aqueous phase comprising one or moresurfactants, mixing together the organic and aqueous phases, and thenemulsifying.
 8. The dispersion according to claim 7, wherein the organicphase comprises a liquid compound (at 20-25° C., 1 atm.) that isinsoluble in water and is solubilizing for the copolymer, wherein thecompound is selected from the group consisting of: linear or branched,saturated or unsaturated, optionally cyclic or aromatic C5-C30 alcoholsor polyols, which optionally contain heteroatoms; esters of monoalcoholsor polyols and of monoacids or polyacids, and triglycerides and estersof general formula R3-O—CO—R4, in which R3 and R4, which are optionallyidentical or different, are linear or branched, or even cyclic,saturated or unsaturated, C3-C30 hydrocarbon-based radicals; ketones ofthe type R3-CO-R4 in which R3 and R4, which are optionally identical ordifferent, are linear or branched, or even cyclic, saturated orunsaturated, C3-C30 hydrocarbon-based radicals; aromatic hydrocarbons;linear, cyclic or branched C5-C30 alkanes; and volatile or non-volatilesilicone oils.
 9. The dispersion according to claim 7, wherein thesurfactant is a cationic surfactant.
 10. A cosmetic compositioncomprising at least one aqueous dispersion of polysiloxane/polyureacopolymer according to claim
 1. 11. The cosmetic composition accordingto claim 10, wherein the amount of copolymer is between 0.01% and 30% byweight of polymer solids relative to the weight of the cosmeticcomposition.
 12. The cosmetic composition according to claim 10, whichis in the form of a product for caring for, cleansing and/or making upbodily or facial skin, the lips, the eyebrows, the eyelashes, the nailsand the hair, an antisun or self-tanning product, a body hygieneproduct, or a haircare product.
 13. A cosmetic treatment process,comprising applying a cosmetic composition according to claim 10 tomaking up, caring for, cleansing, colouring or shaping keratinmaterials.
 14. A kit in two or more parts, comprising at least onecosmetic composition according Claim
 10. 15. A process for preparing anaqueous dispersion of polysiloxane/polyurea copolymer according to claim1, comprising: dissolving the copolymer and the silane in an organicphase, preparing an aqueous phase comprising one or more surfactants,mixing together the organic and aqueous phases, and then emulsifying.